Tears and bursitis:

Firstly, the evidence is clear that no obvious causative link exists between rotator cuff tears, both full thickness and partial thickness, and shoulder pain symptoms. This has been borne out by multiple studies:

In one study, of 212 asymptomatic individuals, MRI confirmed a complete rupture of the supraspinatus tendon in 90% of patients. All patients reported no functional deficits (Schibany 2004).

In Sher et al’s (1995) study, the population examined reported a 30% prevalence of asymptomatic rotator cuff tears. Lehman et al found that 17% of cadavers dissected demonstrated tears in a group of individuals with no history of shoulder pain or dysfunction.Conor et al (2003) discovered that, among asymptomatic overhead athletes, 40% had findings consistent with partial- or full-thickness tears of the rotator cuff. 25% had MRI evidence of Bennett’s lesions. Saliently, none of the athletes interviewed 5 years later had any subjective symptoms or had required any evaluation or treatment for shoulder-related problems during the study period.

The conclusion to be drawn from all this is that MRI’s are extremely unlikely to be clinically useful for determining whether pain in a particular patient is the result of an underlying rotator cuff tear. Moreover, presence of rotator cuff tears should certainly not be used as a basis for operative intervention. Rotator cuff tears often remain asymptomatic despite their large size (Tempelhof 1999). And even in patients who are symptomatic with MRI evidence of tears, symptoms typically resolve with conservative treatment anyway (Yamaguchi et al 2001; Baydar et al 2009; Beaudreuil et al 2007). Presently, there is no clear consensus regarding the indications for rotator cuff surgery (Dunn et al 2005; Marx et al 2009), yet over 75,000 rotator cuff repairs are performed annually in the United States alone (Vitale 2007).

Additionally, when verbal MRI results are relayed to patients, this can change the patient’s expectation of their pain, potentially amplifying it. Pain is highly modifiable by expectations, so these misleading scan results only serve to either shroud and mystify the patient’s pain experience, or act as a nocebo and reduce activity and function in concentrically smaller circles, leading to chronicity (Atlas and Wager, 2012).

So that’s rotator cuff tears. What about bursitis you say? Zanetti’s (2000) study identified bursitis-like abnormalities in 100% of all asymptomatic patients studied. Additionally, Zanetti (2000) found that “subacromial bursitis-like MRI abnormalities are almost always seen after rotator cuff repair even in patients without residual complaints. They may persist for several years after rotator cuff repair and appear to be clinically irrelevant.” Additionally, Hogson et al (2014) reported in their MRI study that subdeltoid and subacromial bursitis was common in both asymptomatic and symptomatic patients, and no evidence was found to support the hypothesis that bursitis is associated with pain.

Rotator cuff tears and bursitis as an explanation for shoulder pain simply makes for a good, but fundamentally misleading story. The image that MRI results create in the mind of the patient is also significant. The patient may view themselves as permanently damaged and in serious need of drastic surgery. The evidence is well documented that MRI results could potentially form a mental representation of an impending sensory event, which can significantly shape neural processes that underlie the formulation of the actual sensory experience, potentially worsening symptoms (Koyama et al 2005).

In two functional magnetic resonance imaging (fMRI) experiments conducted by Wager et al (2004), it has been discovered that by increasing a patient’s expectation of pain, observed brain activity in the pre-frontal cortex is amplified. These studies have verified that expectations produce objective brain related changes, subsequently reinforcing a patient’s subjective pain experience.

Other studies have shown that the subject's negative expectations of pain induce an anticipatory anxiety. Anxiety about the worsening pain triggers the activation of cholecystokinin that, in turn, facilitates pain transmission (Colloca 2007).

Patients with underlying or pre-existing anxiety are particularly at risk of complicity with this process. Benedetti et al (2006) has identified a close relationship between anxiety and nocebo hyperalgesia through multiple pain experiments using verbally induced hyperalgesia.

In essence, informing a patient of the results of a shoulder MRI presenting with rotator cuff tears and bursitis basically consists of delivering verbal suggestions of negative outcomes so that certain subjects may then expect clinical worsening (Benedetti 2007). This process underscores an important point of vulnerability in the course of a patient’s treatment, and potential regression to chronicity.

Treatment:

Surgery:

There is no good evidence that commonly performed surgical procedures for rotator cuff impingement perform any better than supervised exercise when tested with long-term randomised control trials. The outcome of a 2 year trial, 5 year trial and systematic review are as follows:

1. “Arthroscopic acromioplasty provides no clinically important effects over a structured and supervised exercise programme alone in terms of subjective outcome or cost-effectiveness when measured at 24 months. Structured exercise treatment should be the basis for treatment of shoulder impingement syndrome, with operative treatment offered judiciously until its true merit is proven.”

2. “Differences in the patient-centred primary and secondary parameters between the two treatment groups were not statistically significant, suggesting that acromioplasty is not cost-effective. Structured exercise treatment seems to be the treatment of choice for shoulder impingement syndrome.”

Unfortunately, to date, there are no randomized controlled studies that compare outcome of surgical vs. conservative treatment of atraumatic rotator cuff ruptures (Heerspink 2011). Various studies have examined clinical outcomes post rotator cuff repair surgery. Authors such as Cofield et al (2001) have suggested that surgical repair of the torn rotator cuff is effective in reducing pain. Saliently, however, these studies do not examine a control group that has their expectations adequately raised to invoke the same potential placebo response as the surgical group. The current science of chronic pain suggests that these individuals, most likely, responded to the placebo effect of surgical intervention. The ingrained cultural associations of hospitalisation and surgery, and the psychological meaning of these interactions may directly shape the interpretation of pain through altered neurological processes, and changing personal contexts (Guess et al 2002).

The placebo patients in these studies were put to sleep, draped, examined, injected with local anaesthetic, and then given an incision to mimic real surgery (Guess et al 2002). In these studies, patients receiving the sham procedures responded essentially the same or better as those who received the full surgical treatment (Guess et al 2002). Results from these studies are consistent with the notion that medical acts are culturally meaningful, and that meaning has an effect on patients (Guess et al 2002). Surgery is particularly meaningful: surgeons are among the elite of medical practitioners, and typically hold prestigious positions in society. In addition, surgical procedures such as rotator cuff repairs, for the lay person, may have a compelling rational explanation “we’ll repair the torn tendon, clean out the joint and thereby alleviate your pain”(Guess et al 2002).

The point here is not whether the patients feel better after the full rotator cuff surgery, but why they feel better, whether intellectual honesty prevails in discussions with these patients, and whether patients are exposed to unnecessary risk through surgery and hospitalisation. Interestingly, studies such as that by Cofield et al (2001), still try and describe the benefit of rotator cuff repair with mechanical explanations. Given what we know about the science of chronic pain, placebo/nocebo interactions and culturally generated meaning responses, and given what we know about the lack of proven causality between rotator cuff tears and symptoms, this type of reasoning seems patently obsolete.

Exercise and yoga therapy:

Honest discussion with patients about the factors outlined above is imperative in sound management of rotator cuff impingement, and rotator cuff tears. Personalised supervised exercise needs to be encouraged as the primary treatment, as it supported by the current evidence.

The most effective exercise is supervised and personalised exercise that has several components. The exercise treatment should include techniques to modulate anxiety. Since pain appears to be amplified by anxiety through the activation of cholecystokininergic systems, strategies to reduce anxiety, such as yoga therapy, can be applied whenever pain has an important anxiety component. According to Streeter et al (2007), a regular practice of yoga releases a neurotransmitter chemical called GABA. Individuals who exhibit increased anxiety have reduced levels of GABA. The authors believe that these sustained levels of GABA over a period of regular yoga practice may help the brain to rewire itself, reducing anxiety and thereby modulating the pain response.

Additionally, exercise that is able to address scapular muscle dysfunction may be helpful. Warner et al (1992) discovered that scapular muscle dysfunction is common with both instability and impingement syndrome of the shoulder.

Lukasiewicz et al (1999) has also identified that altered scapular kinematics may be an important aspect of the impingement syndrome.

However, at present, it is not clearly understood whether these musculoskeletal factors represent a primary or secondary phenomenon. However, there is good quality evidence that supports the role of “neurocognitive” exercise, such as yoga therapy, in treating shoulder impingement syndrome. Marzetti et al (2014) found that neurocognitive rehabilitation that includes proprioception and neuromuscular control is effective in reducing pain and improving function in patients with shoulder impingement syndrome, with benefits maintained for at least 24 weeks.

Conclusion:

The evidence suggests that an integrated approach to exercise rehabilitation that includes practices at the biomechanical, respiratory, and cognitive levels, applied individually and in a graded manner is supported by the current evidence as the treatment of choice for shoulder impingement syndrome. In this context, personalised yoga therapy will address underlying musculoskeletal imbalances, nervous system dysfunction, soft tissue remodelling, and cognitive aspects such as central sensitisation and anxiety related issues that promote chronicity in shoulder pain patients. Additionally, general improvement in quality of life with exercise based interventions such as yoga therapy has been observed with many chronic pain conditions, and its mechanisms are underscored by a basis grounded in biomechanics and the current scientific understanding of pain perception and neuroscience (Da Silva et al 2007; Haslock et al 1994; Raghavendra et al 2008).

15. Koyama, T., McHaffie, J. G., Laurienti, P. J., & Coghill, R. C. (2005). The subjective experience of pain: where expectations become reality. Proceedings of the National Academy of Sciences of the United States of America, 102(36), 12950-12955.